Proximal Femur and Pelvis

What kind of joint is the hip joint?

diarthrodial, synovial, ball and socket

What is the small indentation on the head of the femur?

fovea capitis

What ligament attaches in the fovea capitis?

ligament capitis femoris (teres)

Explain the direction that the head/neck of the femur projects

• medially

• superiorly

  • 120-130^o (more angle on a taller person) to the long axis of the shaft

• anteriorly

  • 15-20^o (more angle on a taller person) from the shaft

Explain the location of the greater trochanter

on the lateral surface of the femur at the junction of body and base of neck

What other anatomical level does the greater trochanter coincide with?

level of the upper margin of the pubic symphysis

Explain the location of the lesser trochanter

on the posteromedial margin of the femur at the junction of the neck and shaft

How should the feet be positioned for a true AP of the pelvis?

internally rotated 15-20^o

Where is the intertrochanteric crest located?

(prominent ridge) on the posterior surface of the femur between trochanters

Where is the intertrochanteric line located?

(less prominent ridge) on the anterior surface of the femur between trochanters

Where should you center for a hip x-ray?

femoral neck

How do you find the location of the femoral head?

draw a line between ASIS and pubic symphysis, 1½ inches perpendicularly distal to the middle of that line

How do you find the location of the femoral neck?

draw a line between ASIS and pubic symphysis, 2½ inches perpendicularly distal to the middle of that line

How do you find the location of the acetabulum?

draw a line between ASIS and pubic symphysis, acetabulum is at the middle of that line

Why do you need to rotate feet internally 15-20^o for an AP hip?

to not foreshorten femoral neck and to superimpose the lesser trochanter

How is a patient positioned for a frog lateral hip?

hip flexed 90^o and leg abducted 45^o

What is a contraindication for doing a frog lateral hip?

hip fracture

What is the name for the “true lateral” hip view?

Daniellus Miller

Explain the Daniellus Miller view

• shoot-thru lateral of the hip (trauma or post-op)

• IR parallel to femoral neck

• CR perpendicular to femoral neck

• raise unaffected leg

What bones make up the pelvic girdle?

right hip bone and left hip bone

What bones make up the pelvis?

right hip bone, left hip bone, sacrum, and coccyx

What are 2 other names for the hip bone?

os coxae and innominate bone

List and explain the location of the 3 bones that make up the hip bone

ilium - superior

ischium - posterior

pubis - anterior

Where do the 3 bones of the os coxae connect?

acetabulum

What fraction of the acetabulum is made up by the ilium? ischium? pubis?

ilium - 2/5

ischium - 2/5

pubis - 1/5

What is the body of the ilium?

the thick, inferior portion closest to the acetabulum

What is the ala of the ilium?

the “wing” that projects superiorly

The auricular surface of the ilium articulates with the ___

sacrum

What is another name for the arcuate line?

medial line

What is the body of the ischium?

the thickened posterior portion that helps make up the acetabulum

What is the ramus of the ischium?

forms the inferior border of the obturator foramen; passes anteriorly from the ischial tuberosity

What is the ischial tuberosity?

a palpable landmark that supports weight when sitting; the most inferior structure of the pelvis

Where is the ischial tuberosity located relative to the pubic symphysis?

tuberosity is 1-2 inches inferior to symphysis

What is the ischial spine?

a pointed process on the ischium that extends medially and is situated between the greater and lesser sciatic notches

What anatomical structure is outlined in blue?

ischial spines

Is this a right or a left hip bone?

left

What is the body of the pubis?

the part that forms the anterior/inferior 1/5 of the acetabulum

Explain the superior and inferior pubic rami

superior: extends anterior from the body and forms the upper border of the pubic symphysis

inferior: extends down from superior ramus and joins the ischial ramus

What is the articular surface of the pubis?

the part that connects to the other pubis at the pubic symphysis

What anatomical structure is outlined in blue?

pubic arch

What makes up the obturator foramen?

pubis (body and rami) and ischium (body, ramus, and tuberosity)

What is the largest foramen in the human body?

obturator foramen

A. ala

B. acetabulum

C. greater trochanter

D. neck

E. lesser trochanter

F. ischial tuberosity

G. superior pubic rami

H. ischial rami

What kind of joint is at the acetabulum?

cartilaginous (triradiate cartilage), amphiarthrodial, synchondrosis

What anatomical structure of the acetabulum is at each color?

blue: rim

pink: fossa

green: notch

What part of the acetabulum is the articular surface?

rim

When does ossification of the acetabulum complete?

at 18 years old

The acetabular rim is made up of the ___ and ___

anterior and posterior walls

What is the pelvic brim?

oblique plane that divides the pelvis into a superior and inferior part

What makes up the pelvic brim?

iliopectineal line, arcuate line, and anterior sacrum

What does the red circle represent?

the pelvic inlet

What does the red circle represent?

the pelvic outlet

What is another name for the pelvic brim?

linea terminalis (terminal line)

Explain the location of the greater pelvis

• superior to the pelvic brim

• lateral and posterior limits are formed by the ala

• anterior limit is formed by abdomen

What is the “false pelvis”?

the greater pelvis

What is the “true pelvis”?

the lesser pelvis

What is the function of the greater pelvis?

support lower abdomen organs

What is the function of the lesser pelvis?

forms the birth canal

Explain the location of the lesser pelvis

• inferior to the pelvic brim

• “pelvic cavity” - the area between the inlet and outlet

• contains reproductive organs, urinary bladder, pelvic colon, and rectum

Explain the pelvic inlet

• superior aperture of the true pelvis

• formed by the brim of pelvis (top of sacrum to symphysis)

Explain the pelvic outlet

• inferior aperture of the true pelvis

• triangular shape (end of coccyx to the right and left ischial tuberosities)

What is measured to find the longitudinal diameter of the pelvic outlet?

tip of coccyx to right and left ischial tuberosities

What is measured to find the transverse diameter of the pelvic outlet?

space between the ischial spines

How was the birth canal measured in the past?

pelvimetry

How is the birth canal measured now?

ultrasound

What tube angle is used for pelvic inlet views?

What tube angle is used for pelvic outlet views?

inlet: caudal

outlet: cephalic

Where are the sacroiliac (SI) joints located?

at the articulation of the articular surfaces of the sacrum and ilium

What type of joint are the SI joints?

synovial, diarthrodial, gliding

How do you demonstrate the SI joints?

25-30^o oblique

if AP, side up is demonstrated

if PA, side down is demonstrated

The pubic bones are separated by ___

a pad of fibrocartilage

What type of joint is the pubic symphysis?

cartilaginous, amphiarthrodial, symphysis

What makes up the hip joint?

head of femur and the acetabulum of the os coxae bone

What type of joint is the hip joint?

synovial, diarthrodial, ball and socket

What is another name for the hip joint?

coxal joint

Explain the 3 main differences between a male and female pelvis

• shape

  • female is broader, wider, and flared

  • male is narrow and less flared

• pubic arch

  • female is >90^o

  • male is <90^o

• inlet

  • female is larger and oval

  • male is smaller and round

What needs to be included on an AP pelvis image?

from greater trochanter to greater trochanter and from top of crest to ischial tuberosities

What are some causes for congenital hip dislocation?

• abnormal formation

  • low amniotic fluid

  • confinement in utero

  • breech position

• loose ligaments

Explain osteoarthritis

• the most common type of arthritis leading to hip replacements

• break down of the cartilage that cushions the joint

  • aging

  • prior trauma

  • congenital abnormalities